diff --git a/lvk/LVK.h b/lvk/LVK.h
index cfb7a597da..07ea2be083 100644
--- a/lvk/LVK.h
+++ b/lvk/LVK.h
@@ -808,6 +808,13 @@ enum AccelStructGeometryFlagBits : uint8_t {
   AccelStructGeometryFlagBits_NoDuplicateAnyHit = 1 << 1,
 };
 
+enum AccelStructInstanceFlagBits : uint8_t {
+  AccelStructInstanceFlagBits_TriangleFacingCullDisable = 1 << 0,
+  AccelStructInstanceFlagBits_TriangleFlipFacing = 1 << 1,
+  AccelStructInstanceFlagBits_ForceOpaque = 1 << 2,
+  AccelStructInstanceFlagBits_ForceNoOpaque = 1 << 3,
+};
+
 struct AccelStructBuildRange {
   uint32_t primitiveCount = 0;
   uint32_t primitiveOffset = 0;
@@ -815,6 +822,19 @@ struct AccelStructBuildRange {
   uint32_t transformOffset = 0;
 };
 
+struct mat3x4 {
+  float matrix[3][4];
+};
+
+struct AccelStructInstance {
+  mat3x4 transform;
+  uint32_t instanceCustomIndex : 24 = 0;
+  uint32_t mask : 8 = 0xff;
+  uint32_t instanceShaderBindingTableRecordOffset : 24 = 0;
+  uint32_t flags : 8 = AccelStructInstanceFlagBits_TriangleFacingCullDisable;
+  uint64_t accelerationStructureReference = 0;
+};
+
 struct AccelStructDesc {
   AccelStructType type = AccelStructType_Invalid;
   AccelStructGeomType geometryType = AccelStructGeomType_Triangles;
@@ -827,6 +847,7 @@ struct AccelStructDesc {
   IndexFormat indexFormat = IndexFormat_UI32;
   BufferHandle indexBuffer;
   BufferHandle transformBuffer;
+  BufferHandle instancesBuffer;
   AccelStructBuildRange buildRange = {};
   uint8_t buildFlags = AccelStructBuildFlagBits_PreferFastTrace;
   const char* debugName = "";
diff --git a/lvk/vulkan/VulkanClasses.cpp b/lvk/vulkan/VulkanClasses.cpp
index badb7e5c3a..a546ad3eac 100644
--- a/lvk/vulkan/VulkanClasses.cpp
+++ b/lvk/vulkan/VulkanClasses.cpp
@@ -38,6 +38,7 @@ static_assert(lvk::Swizzle_R == (uint32_t)VK_COMPONENT_SWIZZLE_R);
 static_assert(lvk::Swizzle_G == (uint32_t)VK_COMPONENT_SWIZZLE_G);
 static_assert(lvk::Swizzle_B == (uint32_t)VK_COMPONENT_SWIZZLE_B);
 static_assert(lvk::Swizzle_A == (uint32_t)VK_COMPONENT_SWIZZLE_A);
+static_assert(sizeof(lvk::AccelStructInstance) == sizeof(VkAccelerationStructureInstanceKHR));
 
 namespace {